1. Field of the Invention
The present invention relates to a process of attrition which is carried out in a humid medium. More specifically, this invention relates to a process for the attrition of previously ground ores. It also relates to an apparatus for carrying out this process.
2. Description of the Prior Art
Attrition through a humid (wet) method consists of submitting ore grains which are dispersed in water to friction and blows, the force of which is too weak to produce grinding, but nevertheless sufficiently high to free the softest portions. These portions are recovered in the aqueous phase in the form of very fine particles. The attrition not only permits the separation of the soft particles, but also it produces new particles from the friction and blows among the particles.
Certain industries currently employ a different technique, which is also called attrition, but this does not create new particles. This is especially the case in the glassmaking industry where a technique called attrition is used to wash sand, in this case, only a separation is sought.
In addition, these techniques, which are improperly called attrition, do not produce satisfactory results when one wishes to treat materials such as, for example, a nickel ore. Furthermore, they consume large amounts of energy. In the case of attrition of a nickel ore, for instance, it is necessary to use 80 kilowatts per ton of ore treated to obtain a return of 30% in weight of particles created by attrition.